Page 287 - Concise Pathology for Exam Preparation ( PDFDrive )

272 SECTION II Diseases of Organ Systems

(b) Common serologic tests done are
(i) Antistreptolysin O (ASO) levels: Single titer of ASO more than 200 Todd units
in adults and 300 Todd units in children above 5 years, are taken as positive.
However, a rising titer is even more significant.
(ii) Anti-DNase B levels
(iii) Antihyaluronidase (AH) levels
(iv) Antistreptozyme test (ASTZ) levels: Very sensitive indicator of recent strepto-
coccal infection. Titers more than 200 U/mL are considered positive
3. Acute phase reactants: These tests confirm the presence of an inflammatory process,
but are nonspecific:
(a) Raised erythrocyte sedimentation rate (ESR)
(b) Increased C-reactive protein (CRP)
4. Haematologic abnormalities and levels of serum proteins:
(a) Neutrophilic leukocytosis
(b) Increase in serum complement level
(c) Increase in serum mucoproteins, alpha-2 and gamma-globulin levels
(d) Anaemia due to suppression of erythropoiesis
5. Electrocardiogram: The most consistent abnormality is prolongation of the PR interval.
6. X-ray chest: Evidence of cardiac failure may be seen, like:
(a) Cardiomegaly
(b) Pulmonary congestion
7. Echocardiography: Echocardiography may show
(a) Myocardial dysfunction
(b) Valvular dysfunction
(c) Pericardial effusion
Jones criteria for diagnosis of acute rheumatic fever are summarized in Table 11.4.

TABLE 11.4. Diagnosis of acute rheumatic fever (Jones criteria)
Major manifestations Minor manifestations
Carditis Fever
Polyarthritis Arthralgia
Chorea Previous rheumatic fever or rheumatic heart disease
Erythema marginatum Raised ESR
Subcutaneous nodules Positive CRP
Prolonged PR interval (first-degree A–V block)

Supporting evidence of preceding streptococcal infection includes:
1. Recent scarlet fever
2. Positive throat culture for group A streptococcus
3. Increased streptococcal antibodies
Two major manifestations or one major and two minor manifestations, along with at
least one supporting evidence, indicate a high probability of rheumatic fever.

Q. Classify endocarditis. Write briefly on the
clinicopathological features of the various types of
endocarditis.
Ans. Endocarditis is the inflammatory involvement of the endocardial layer of heart in-
cluding valves, chordae and papillae.
Classification

1. Noninfective
(a) Rheumatic endocarditis (see answer to previous question)
(b) Atypical verrucous (Libman–Sacks) endocarditis
(c) Nonbacterial thrombotic (NBTE) or marantic endocarditis

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